I have pages in a pages library on a publishing site which have a managed metadata (taxonomy) field in their content type. I want my custom search webpart to read the taxonomy set on its parent page (I can do this fine) and then query against a specific scope using only the selected tags of the parent page as the filter (no keyword necessary).

I have tried to set FixedQuery = “owstaxIdMetadataAllTagsInfo=#0[TERM GUID]” of my CoreResultWebPart with no success...
I actually gave up after I was getting 0 results and am now trying to just perform a FullTextSqlQuery.

Unfortunately it seems that even though pages with the managed metadata field are successfully being indexed, the managed property owstaxIdMetadataAllTagsInfo has no data in the results! I went ahead and made the property searchable/queryable and the property value is null.

Can you anyone confirm that I should be getting values from that managed property when there is indeed a managed metadata field on the page that is populated with data?

Note: I have tried to make my own managed property based on the managed metadata field in my site's content type -- same results.